Find the Celsius temperatures corresponding to (a) a winter night im Seattle $\left(41.0^{\circ} \mathrm{F}\right) ;(\mathrm{b})$ a hot summer day in Palm Springs $\left(107.0^{\circ} \mathrm{F}\right) ;(\mathrm{c})$ a cold winter day in northern Manitoba $\left(-18.0^{\circ} \mathrm{F}\right)$ .